In optical communication networks, optical modules transmit and/or receive optical signals in optical fibers. The optical receiving module is an optical module that receives optical signals, but does not transmit optical signals. The optical transmission module is an optical module that transmits optical signals, but does not receive optical signals. The optical transceiver module is an optical module that transmits and receives optical signals. As the demand for data throughput increases, the data rate or bandwidth of optical fiber networks is also increasing. A conventional technology is to transmit and receive optical signals of different wavelengths on each optical fiber, which is commonly referred to as bidirectional (BiDi) communication.
However, the design and manufacture of multi-channel optical modules with BiDi functions requires accurate optical alignment between the light source and the optical components.